Brief Summary

Koala lemur (Megaladapis)

The koala lemur [1,2] is a genus of lemur belonging to the extinct family Megaladapidae. It lived in Madagascar. Fossils have been found around the marsh of Ambolisatra on the southwestern side of Madagascar. Charles Immanuel Forsyth Major‭ ‬named the genus 'Megaladapis' in‭ ‬1894.

It had a squat body like a koala. Its long arms, fingers, feet, and toes were specialized to grasp trees and its legs were splayed for vertical climbing; the hands were well adapted to grasp vertical trunks of trees. The hands and feet were curved and the ankles and wrists did not have the usual stability needed to travel on the ground that most other Lemurids have [3]. Unlike other primates, the eyes were on the sides of its skull, instead of forward; it‭’‬s probable that the lemur lacked the acute depth perception of other primates.‭ It had long canines and a cow-like jaw formed a tapering snout. Its jaw muscles were powerful to chew tough vegetation. Its nasal region showed similarities to those of rhinoceros, which probably combined with the enlarged upper lip to grasp leaves. The brain capacity was about 250cc [4]. The largest species reached 1.3-1.5 m long and up to 50kg. The lemur specialized within its own niche. As this tree climber grew larger, its forelimbs increased proportionally [5]. It was diurnal and moved slowly, having a more gradual pace of life rather than the fast paced leaping from tree top to tree top of some smaller primates. Despite its large size,‭ ‬Megaladapis is thought to have been an arboreal creature that lived off the ground where it could casually browse upon the vegetation of the tree canopy.‭

Some people believe that Malagasy legends of the tretretretre or tratratratra refer to Megaladapis, but details of the tales, notably the "human-like" face of the animal, match the related Palaeopropithecus much better [6].

When humans arrived, 1,500-2,000 years ago, they cleared large areas of the island using "slash-and-burn" techniques. Megaladapis couldn't adapt to the environmental changes and the presence of humans and became extinct about 500 years ago.It moved slowly and was probably very susceptible to predators, forest fires, habitat destruction and possibly introduced pathogens [7]. The major cause of extinction was human activity,‭ ‬particularly habitat destruction from expanses of forest being cleared by fire; human hunting also probably played a factor in its demise.

The three species were M.‭ ‬edwardsi,‭ ‬M.‭ ‬madagascariensis and‭ ‬M.‭ ‬grandidieri.